Philip, the husband of Queen Elizabeth II, was admitted to a London hospital on Tuesday night after feeling ‘bad’, Buckingham Palace announced earlier this week.
“As we said earlier, the doctor is acting with an abundance of caution. The Duke remains in a good mood,” the source said Friday.
The exact reason for the admission was not disclosed.
The 99-year-old retired from public life in 2017 and has been taken to hospital several times in recent years. In December 2019, he received hospital treatment for an existing condition.
According to a royal source, his latest admission was not an emergency and the duke traveled by car to King Edward VII Hospital and walked in without assistance. The source added that the disease is not related to Covid-19.
The queen was staying at Windsor Castle in west London at the time.
Prince Philip and Queen Elizabeth both received at least one dose of Covid-19 vaccine.
Earlier Friday, Buckingham Palace announced that Prince Harry and Meghan, Duchess of Sussex, would not return as working members of the royal family.